Vacuum clamping device for stave columns.



PATENTEU JULY 14 C. W. LCCCIB.l VACUUM CLAMPINC DEVICE PCR STAVECOLUMNS.

- APPLICATION FILED NOV. 4. 1907.

INVENTOR n .CZ/4% ATTORNEY GEORGE W. LOGGIE', OF BLIJING'HAM,WASHINGTON.

VACUUM CLAMPING DEVICE FOR sTAvE'eoLUMNs.

Specification of Letters Patent.

Patented July 14, 1'908.-

Application :filed November 4, 1907. Serial No. 400,696.

To all whom 'Lt may concern:

Be it known that I, GEORGE W'. LoGGIE, a

citizen of the United States, and a resident of Bellingham, in thecounty of Whatcom and State of Washington, have invented certain new anduseful Improvements in Vacuum Clamping Devicesfor Stave Columns, ofwhich the following is a s eciiication.

My invention re ates to an improvement in devices for clamping stave,porch columns in which the clam s must retain the staves in proper placein t e column while the glue with which their matched surfaces have beensmeared in setting. The present practice is to confine the assembledstaves in metallic band or chainclamps and tighten the same with eitherscrews or a cam lever. l A number of these clamps are required toproperly draw the staves together, necessitating considerable time intheir adjustment, tightening and removal. Also these chains or bandssink into the wood causing more orless disgurement to the surface. In mydevice I close the ends of the hollow column with -air tight caps, thenexhaust the airfrom the interior of the column. and maintain this vacuumuntil the glue has hardened sufiiciently to retain the staves together.Thus I entirely dispense with the clam s ordinarily used. The devicewith whichil accomplish this object is illustrated in the accompanyingsheet of drawings in which similar characters referto similar partsthroughout. l

Figure l is an end elevation of a device in which the columns areassembled and receive the air tight caps. Fig. 2 is a front elevation ofFig. 1. Fig. 3 is a front elevation of an air pump with connecting pi esand certain fixtures for holding the yco umns while they are under airpressure. And Fig. 4 is a plan view of said fixtures.' A portion of Fig.1 is removed for lack of space; certain other parts are also removed inorder to better show the parts lying beneath. For the same purposecertain parts are also removed in Figs. 2 and 3.

In Figs. 1 and 2, 1, 2 and 1, 2 are supports for the shears 3, 3. 4 is ahead-stock with a deep recess 41 for receiving the cap8. Headstock 4 issecured to the shears 3, 3 by clamp 4 and clamp screw 4". Tail-stock 5`has a deep recess 51 for receiving the cap 8 and is retained on theshears by the clamp 5 and clamping, hand-wheel screw 5". There is `oneof said standards.

1 also a tail-screw 7 suited to work in tailstock 5. Forms 6, 6 areclamped to the shears by clamps 6 6 and clamp screws 6, 6". The stavecolumnjillustrated is composed of eight, similar, tapering staves ofequal length. These staves are, matched with V form tongues and groovesand are slightly crowned in the center'. No attempt has been made toshow said enlargement 1n the center because it is ordinarily too smallto be illustrated in the scale used. These staves A, A, A, A, and fourothers not designated by characters, are iirst smeared with glue ontheir matched edges and roperly assembled in forms 6, 6. Cap 8 is p acedin the deep recess 4'1 in head-stock 4 and the larger end of the looselyassembled column is shoved into its flaring recess 81 in the bottomofwhichis the rubber gasket 9. Cap 8 which has a iiarin recess 81similar to 81 in ca 8, and in the ottom of which is also a rub er gasket9, is placed in the deep recess 51 in tail-stock 5. Tail-stock 5 isadvanced toward the column until the smaller end of said column hasentered the recess 81 in cap 8 and then said tail-stock is clamped tothe shears by turning hand-wheel 5". Tailscrew 7 is then turned untilthe ends of the column A, A, A, A are rammed home in caps 8 and 8', withthe'ends of said column closely .when the ends of the column are forcedtherein the staves composing said column are brought snugly together,yet the fit of said caps is not so tight but that they may afterwards beeasily removed with a few blows of a hammer. In the center of recess 81in cap 8 stands the boss 80. In this boss, opening outward, is thecylindrical recess 8 with a conical entrance. Through the walls of thisboss is the central hole O. Also lying on the bottom of the recess 8 isthe rubber gasket 9. I

Figs. 3 and 4 show .two standards 10, 10. These consist of the foot part12, the body 10 and the cylindrical top 11. This cylindrical top issuited to make an easy it in the recess 8 in cap 8 and fitsnugly'against thegasket 9. In these standards are the holes O', O whichare so placed as to register with hole O in cap 8 when said cap isplaced on Hole O passes downward into the standard, turns at rightangles and makes an outlet through the body 10 of the same. l nectedwith the said outlets of holes O, O in standards 10, 10, also withvacuum tank 13 and air pump 14 in Fig. 3. The interior valves necessaryfor the proper working of air pump 14 are not shown 1n thisillustration.

In the branches of the system of pipes 20 leading from the main line tothe standards 10, lOare the two-way cocks 15, 15. These are providedwith inlet tubes 19, 19 Fig. 3 and are located nearest said standards.They are so constructed that when opened to the passage of air throughthe'pipes 2O they are closed to the passage of air through tubes 19 andvice versa. Also in said branch pipes are the valves 16, 16. On anotherbranch ipe from main line pipe 20 is a branch leading into the vacuumtank 13, Fig. 3. Valve 18 is placed in this branch. In main-line -pipe2O near air pump 14 is a valve 17. In practice I use a number ofstandards 10, 10 connected with main line pipe 20, but for the purposeof this description only two are shown.

After the caps 8, 8 have been placed on a stave column as shown in Figs.1 and 2, the column with said caps in place is put, cap 8 downward, on astandard 10 with top 11 of said standard in the cylindrical recess S insaid cap. Thus placed the capped column is retained in a verticalposition4 on said standard. Also the top 11 of said standard fits snuglyagainst the gasket 9, thus making an air lock at this point. Then sincethe ends of the staves are pressed snugly against gaskets 9 and 9, thehollow columns placed on the standards, as shown in Fig. 3, are properlyprepared to have the air exhausted from their interior. This isaccomplished by running the air pump 14 with valves 16, 16 and 17 openand cocks 15, 15 closing inlet pipes 19, 19. Vacuum tank 13 is includedin the pipe system in order to have a reserve vacuum in addition to thepumping capacity of the air pump. The stave columns thus placed underatmospheric pressure are powerfully and evenly compressed over theirentire surface, thus bringing all matched surfaces snugly together, andin this position they are retained until the glue has set suflicientlyto hold them. Then each column is removed by first closing valve 16 thenopening cock 15 when air will enter the column and it may be easilyremoved from the standard. Caps 8 and 8 are then removed and the columnis ready for turning down to finished form.

My method vof clamping stave columnss a herein described does not marthe surface of said columns as is the case with the clamps ordinarilyused, is more rapid in operation, and because of the vacuum maintainedThe system of pipes 20 is conwithin the column, the glue sets morequickly than it does under ordinary atmospheric pressure.

I may vary the herein described method and machinery in details ascircumstances require without passing beyond the limits of my inventionwhich consists in,-

1. A vacuum clamping device used in manufacturing stave columns in whichis combined means for holding a number of staves assembled in columnarform; means for hermetically sealing the ends of said stave columns; andmeans for exhausting the air from within said stave columns.

2.' In a vacuum device for clamping stave columns, the combination ofleg frames; parallel guides or shears resting on and securely attachedto said leg frames; a headstock and a tail-stock suited to stand uponand slide upon and between said shears; a cylindrical recess with wideflaring entrance in each of said stocks, said recesses being centrallylocated and when said stocks are facing each other said recesses beingopposite each other and concentric; clamps and screws for fastening saidstocks to any desired location on said shears; a tail screw centrallylocated in said tail-stock; two or more forms to stand upon and slideupon and between said shears, said forms being provided with screwclamps for making fast to said shears and having a concave,semicircular, upper surface concentric with the recesses in said stocks,said forms holding a number of staves, of equal length and properlymatched to form a column, assembled in columnar form; a cap, with acylindrical or slightly conical recess with wide flaring entrance, ofsuch size that it may nest in the recess in said head-stock, said caphaving a central boss in said recess, and said boss having a central,cylindrical recess entering from the outside of said cap and a centralhole piercing the top wall of said boss; a resilient gasket in thebottom of the recess in said cap and around said boss; a resilientgasket in the bottom of said recess in said. boss, said gasket having acentral hole concentric with the hole piercing the top of said boss; acap, with a cylindrical or slightly conical recess with wide fiaringentrance, of such size that it may nest in the recess of said.tail-stock; a gasket of resilient material in the bottom of said recessin said cap; a standard consisting of a foot, body and top parts, saidfoot being suited to be fastened to the floor, said top part beingsuited to loosely fit into the cylindrical recess in said boss in saidcap, a hole passing from the center of the upper surface of said topthrough said standard to a place where it ends in a tapped part toreceive a pipe; an air pump with suitable power connections, said pumpbeing connected by a line of pipes to said standard, there being atWo-Wacock Signed at Bellingham in the county of in said line of pipes next tosaid stan ard, a Whatcom and State of Washington this 26th Valve next tosaid two-Way cock, and a valve dayr of October A. D. 1907. next to saidair pump; and a vacuum tank GEORGE W. LOGGIE.

5 connected through a pipe with said line of Witnesses:

pipes, said connecting pipe is provided with R. S. SIMPSON, a Valve.DAVID E. LAIN.

